Class ImmutableItemNode

This class is a thread safe version of ItemNode class.
It replicates most of the code in ItemNode but makes
sure it does not modify state of the object.
Therefore multiple request threads can access the
properties of the objects of this class,in a thread safe
manner.
Please note that setters should not be called on objects
of this class.Objects of this class are fully initialized
on construction.

getDestination

Gets the value of the node's destination property.
The destination attr value could be one of 2 things:
1) a uri
2) An EL expression
So that the model can identify this node as the currently selected
node, the node's id is appended to the destination as a parameter
that is picked up when the getFocusRowKey() method of the model
is called to get the focus path.

actionListener

doAction

Gets the value of the node's action property. The action attr value
could be one of 2 things:
1) An EL expression
2) An outcome referencing a navigation rule in the faces_config file.
Since this method is called only when an ItemNode is clicked, the model
is notified that this node is the currently selected node.